Tools exist for producing computer-implemented graphical models, such as graphical block element based models, for example, and/or non-graphical models, such as text-based models that may be executable, for example, by means of numerical simulation. Using the tools, models are created, edited, and may be executed within a computing system. However, inspection, review, and annotation of these models may take place primarily outside of the computing system. For example, models may be printed as hard copies on paper and marked-up by hand. Changes annotated on the hard copy of the model are used to edit the electronic version of the model, with the user/human editor referring back and forth between the screen on which the model is displayed and the hard copy. To test changes made to a model, the electronic version needs to be changed, often with a duplicate copy being made for each set of changes being tested. If more review is needed after an initial round of changes, the model will need to be printed out once again and reviewed again as described above.